<!--  -->
<template>
  <div id="home">
    <nav-bar class="home-nav">
      <div slot="center">购物街</div>
    </nav-bar>
    <tab-control
        class="tab-control"
        :titles="['流行', '新款', '精选']"
        @tabClick="tabClick"
        ref="tabControl1"
        v-show="isTabFixed"
      ></tab-control>
    <scroll
      class="content"
      ref="scroll"
      :probe-type="3"
      :pullUpLoad="true"
      @scroll="contentScroll"
      @pullingUp="loadMore"
    >
      <home-swiper
        :banners="banners"
        @swiperImageLoad="swiperImageLoad"
      ></home-swiper>
      <recommend-view :recommends="recommends"></recommend-view>
      <feature-view></feature-view>
      <tab-control
        class="tab-control"
        :titles="['流行', '新款', '精选']"
        @tabClick="tabClick"
        ref="tabControl2"
      ></tab-control>
      <goods-list :goodsList="showGoods"></goods-list>
    </scroll>
    <!-- .native修饰符,监听组件事件 -->
    <back-top @click.native="backClick" v-show="isShowBackTop"></back-top>
  </div>
</template>

<script>
import NavBar from "components/common/navbar/NavBar";
import TabControl from "components/content/tabControl/TabControl";
import GoodsList from "components/content/goods/GoodsList";
import GoodsListItem from "components/content/goods/GoodsListItem";
import Scroll from "components/common/scroll/Scroll";
import BackTop from "components/content/backTop/BackTop";

import HomeSwiper from "views/home/childComps/HomeSwiper";
import RecommendView from "views/home/childComps/Recommend";
import FeatureView from "../../views/home/childComps/FeatureView";

import { getHomeMultidata } from "network/home";
import { getHomeGoods } from "network/home";
import { itemListenerMixin } from 'common/mixin.js';

export default {
  data() {
    return {
      banners: [],
      recommends: [],
      goods: {
        pop: { page: 0, list: [] },
        new: { page: 0, list: [] },
        sell: { page: 0, list: [] },
      },
      currentType: "pop",
      isShowBackTop: false,
      tabOffsetTop: 545,
      isTabFixed: false,
      saveY: 0
    };
  },
  mixins: [itemListenerMixin],
  components: {
    NavBar,
    HomeSwiper,
    RecommendView,
    FeatureView,
    TabControl,
    GoodsList,
    GoodsListItem,
    Scroll,
    BackTop,
  },
  created() {
    this.getHomeMultidata();
    this.getHomeGoods("pop");
    this.getHomeGoods("new");
    this.getHomeGoods("sell");
  },
  methods: {
    // 事件监听的相关方法
    tabClick(index) {
      switch (index) {
        case 0:
          this.currentType = "pop";
          break;
        case 1:
          this.currentType = "new";
          break;
        case 2:
          this.currentType = "sell";
      }
      this.$refs.tabControl1.currentIndex = index;
      this.$refs.tabControl2.currentIndex = index;
    },
    backClick() {
      this.$refs.scroll.scrollTo(0, 0, 500);
    },
    contentScroll(position) {
      // 1.判断backTop是否显示
      this.isShowBackTop = Math.abs(position.y) > 1000;

      // 2.判断是否吸顶
      this.isTabFixed = -position.y > this.tabOffsetTop;
    },
    loadMore() {
      this.getHomeGoods(this.currentType);
    },
    swiperImageLoad() {
      this.tabOffsetTop = this.$refs.tabControl2.$el.offsetTop;
    },

    // 网络请求相关的方法
    getHomeMultidata() {
      getHomeMultidata().then((res) => {
        this.banners = res.data.banner.list;
        this.recommends = res.data.recommend.list;
      });
    },
    getHomeGoods(type) {
      const page = this.goods[type].page + 1;
      // 请求商品数据
      getHomeGoods(type, page).then((res) => {
        this.goods[type].list.push(...res.data.list);
        this.goods[type].page++;

        this.$refs.scroll.finishPullUp();
      });
    },
  },
  computed: {
    showGoods() {
      return this.goods[this.currentType].list;
    },
  },
  mounted() {
    // 1.图片加载完成的事件监听
    // const refresh = debounce(this.$refs.scroll.refresh, 10);
    // this.itemImgListener = () => {
    //   refresh();
    // }
    // this.$bus.$on("imageLoad", this.itemImgListener);
  },
  activated () {
    this.$refs.scroll.scrollTo(0, this.saveY, 0);
    this.$refs.scroll.scroll.refresh();
  },
  deactivated () {
    this.saveY = this.$refs.scroll.scroll.y;

    this.$bus.$off('imageLoad', this.itemImgListener);
  }
};
</script>
<style  scoped>
#home {
  /* padding-top: 44px; */
  height: 100vh;
  position: relative;
}
.home-nav {
  background-color: var(--color-tint);
  color: #fff;

  /* position: fixed;
  left: 0;
  right: 0;
  top: 0;
  z-index: 9; */
}

.tab-control {
  position: sticky;
  top: 44px;
}

.content {
  /* height: 300px; */
  overflow: hidden;
  position: absolute;
  top: 44px;
  bottom: 49px;
}
</style>